Electric-arc lamp.



No. 728,902. PATENTED MAY 26, 1903. J. 0. GIRDLESTONE & G. P. G. THORKELIN.

ELECTRIC ARC LAMP.

APPLICATION FILED JUNE 23, 1902.

I0 MODEL. 3 SHEETS-SHEET 1.

No. 728,902. BATBNTED MAY 26, 1908. J. 0. GIRDLEST ONE & G. F. G. THORKELIN. ELECTRIC ARC LAMP.

A PPLIOATION FILED JUNE 23. 1902. K0 IODEL. 3 BHBETSSHEET 2.

No. 728,902. PATENTBD MAY 26, 1903.

J. 0. GIRDLEISTONB & c. F. G. THORKELIN.

ELECTRIC ARC LAMP.

APPLICATION IILBDJUNE 23, 1902.

I0 IODBL. 3 SHEETS-SHEET 3.

UNITED STATES Patented May 26, 1903.

PATENT OFFICE.

JOHN OWEN GIRDLESTONE AND CARL FREDERIK GRIMUR THORKELIN, OF LONDON, ENGLAND.

ELECTRIC-ARC LAMP.

SPECIFICATION forming part of Letters Patent No. 728,902, dated May 26, 1903.

Application filed June 23,1902. Serial No. 112.877. (No model.)

To all whom it may concern.-

Be it known that we, JOHN OWEN GIRDLE- STONE, a subject of the King of England, and CARL FREDERIK GEIMUE THORKELIN, a subject of the King of Denmark, both residing at London, England, have invented certain new and useful Improvements in or Relating to Electric-Arc Lamps, of which the following is a specification.

This invention relates to electric-arc lamps, and has special reference to lamps in which the carbons are placed at an angle to each other converging to a point at which the are is formed, the are being preferably controlled [5 by a magnet.

In arc-lamps according to this invention the carbon-holders are arranged to slide in or on converging guides, which are conveniently in the form of tubes held between fixed top and bottom plates and forming with those plates a rigid frame for the lamp. Each carboo-holder is provided with a spring-controlled drum, to which it is connected by a flexible conductor, and each drum is so ar- 2 ranged that it can turn in one direction under the action of its spring independently of the other drum and of a controlling-brake; but the movement of this brake when the lamp is working causes or allows the simulta- 3o neous movementof boththe dru msforstriking or feeding the arc. The magnet for directing the arc is preferably attached to the bottom plate and may be formed by two iron rods projecting above and below the bottom plate, their upper portions being provided with suitable coils, while their lower extremities support transverse pole-pieces and also have a globe-carrier attached to them. This globe-carrier is in the form of a plate which 0 serves as a guide for the lower ends of the carbons.

In the accompanying drawings,\vhichi1lustrate by Way of example one construction of arc-lamp according to this invention, Figure 1 is a central vertical section. Fig. 2 is a similar view taken at right angles to Fig. 1. Fig. 3 is a transverse section on the line 3 3 of Fig. 1. Fig. 4 is a plan with parts in section on the line 4. 4 of Fig. 1, and Fig. 5 is a side elevation showing the brake-gear. Fig.

6 is a diagram showing the electricalcircuits of the lamp.

In all the figures portions of the mechanism are removed for the sake of clearness.

With reference first to Figs. 1, 2, 3, and 4, A A are convergingguides for the carbonholders B B and are in the form of tubes fastened by sockets A 10 a top plate 0 and a bottom plate 0. Mounted on the bottom plate 0 are two supports or brackets D D, one be-' ing in electrical contact with the plate and the other insulated therefrom. Fixed in these brackets D and D are centers E E (see Fig. 4) and sleeves F F. Between the centers E E is a shaft G, mounted so that it can rotate and having fixed to it ratchet-wheels II and H, the ratchet-wheel H being insulated from the shaft. The fixed sleeve F carries a drum J free to turn upon it, and a similar drum J is carried by the other sleeve F. Each of these drums is attached to its corresponding sleeve by a spring, which is not shown in the drawings, but which can be of spiral or other convenient form, one end of the spring being attached to the drum and the other to the fixed sleeve, say, after the manner of an ordinary clock-spring. Pawls K and K, Fig. 2, serve to connect the ratchet-wheels H and H with their adjacent drums. Attached to or forming part of the ratchet-Wheel H is a brakewheel L, and a weighted arm L, provided with a boss L is rotatably mounted on the shaft G. Pivotally mounted upon this arm is a le ver L to the inner end of which is attached one end of a band or chain L which encir cles the brake-wheel L, its other end being I fastened, as at L Fig. 5, to the arm L.

The carbon-holder B is attached by means of a flexible metallic conductor B which passes over a suitable pulley B to the springcontrolled drum J, and the carbon-holder B is similarly connected to the other springcontrolled drum J. The cord and pulley for lenoids are pivotally connected to a cross-bar or frame M*, which is itself pivoted, as at M to the frame of the solenoids, and this crossbar is connected by a link M to the outer end of the pivoted lever L carried by the weighted arm L On the bottom plate C are two iron rods N N, supporting a plate 0, provided with apertures forming guides for the lower ends of the carbons B B Pole-pieces P P are attached to the rods N N, and the upper ends of these rods are furnished with a winding, (diagrammatically shown at N in Fig. 1,) such winding serving when a current is passed through it to magnetize the rods and the polepieces, thus forming a magnet which will direct the are downward.

The electrical circuits of the lamp are diagrammatically represented in Fig. 6 of the drawings, and it will be seen that the windings N of the electromagnets N N are connected in series with one another and with the series solenoid M of the lamp, although it will of course be understood that these windings N may be connected in any preferred manner. For instance, they may be wound and connected as a shunt.

In Figs. 1 and Zthe lampis shown provided with a small globe R, held up against the plate 0, which is flanged to receive it by a spring B. This construction is one suitable for use with inclosed-arc lamps, but obviously fittings to take a large open globe may be attached to the plate 0.

The operation of the lamp is as follows: The weight of .the carbon-holders is such that without the carbons being inserted the holders will descend in the tubes A A, overcoming the tension of the springs in the drums J and J and the friction between the various moving parts, so that when the lamp hangs ready for trimming the carbon-holders rest upon the plate 0. The carbons are then passed through the holes made for them in J the plate O,inserted into their respective holders, and pushed into the tubes. Vihen the weight of the carbon-holders is taken off the cords B the springs in the drums J J act and rotate the drums, winding up the slack flexible cords, this movement of the drums being in such a direction that the pawls K K pass over the teeth of the ratchet-wheels H H. After the carbons have been pushed right up they are allowed to fall until their points meet. In order to limit the amount of rotation of each drum, so that it is only sufficient to allow the carbon to feed throughout its length and to prevent the spring from uncoiling more than is necessary, a small flexible conductor may be coiled around each of the sleeves F F, one end of this conductor being fixed to the drum and the other to the sleeve, and this arrangement will also prove useful in making a good electrical connection between each drum and its sleeve, (such a flexible conductor is shown at S encircling the sleeve F in Figs. 2 and 4,) or the diameter of the drums maybe so fixed that rather less than one turn of the drum suffices to supply the full length of flexible conductor required. In this case a stop-pin, such as J Fig. 4, may he placed on each drum in such a position that it comes in contact with some stationary part of the frame and stops the drum after it has made about one revolution.

It should be mentioned in connection with the brake-gear that, as shown in Fig. 5, when no current is passing through the lamp the parts are so arranged that the weighted arm L rests upon the frame or upon a projection L provided for the purpose, and the chain or brake-band L is slackened. It now the carbons are,in contact and the current be switched on, the series coil M pulls up its core M and through the action of the link M tips the pivoted lever L and tightens the chain L around the brake-wheel L. Gontinned upward movement of the core M? lifts the weighted arm L turning it about its pivot in the direction indicated by the arrow in Fig. 5. This results in a rotation of the ratchetwheel H in the same direction, and the teeth of the wheel engaging with the pawl K turn the spring-drum J and raise the carbon B, the holder of which is attached by the cord B to that drum. The brake-wheel L and ratchet-wheel H being rigidly mounted upon the shaft G, that shaft is also turned, carrying with it the other ratchet-wheel H, so that the spring-controlled drum J rotates and the other carbon B is lifted in the same way and for the same amount as the carbon B and the are is struck. As the arc lengthens the pull upon upon the core of the series solenoid decreases,while that on the core of the shuntsolenoid increases, so that the link M descends and the weighted arm L turns back until its movement is arrested by its coming into contact with the projection ,L or some other stationary point. As the chain L is still taut during this movement the brakewheel L and ratchet-wheel I-I turn also and allow the drum J to turn back under the weight of the carbon and carbon-holder, thus feeding the arc. As soon as the movement of the weighted arm L is arrested the cou tinned descent of the link M causes a slackening of the chain L and allows the feeding to continue by the further backward movement of the drum J. It will be understood that corresponding movement of the other drum J and its carbon B takes place. This feeding action proceeds until balance is restored between the shunt and series solenoids.

Although it is generally convenient to place the magnets which direct the are above it in order to avoid shadows, yet it will beunderstood that should such an arrangement be desirable for any reason they may be placed below the are or in any other preferred position. Again, although it is convenient to mount the spring-controlled drums on the fixed sleeves F and F, yet the drums might IIO be mounted upon fixed shoulders or bosses forming part of the centers E E.

What we claim as our-invention, and desire to secure by Letters Patent, is

1. In an arc-lamp, the combination of two carbon-holders, converging guides for such holders, two spring-controlled drums each adapted to turn under the influence of its spring in one direction independently of any movement of the other, flexible connections between the holders and said drums, a brake adapted to cause both of said drums to turn together, and an electromagnet controlling the brake, substantially as set forth.

2. In an arc-lamp the combination of carbon-holders, converging guides forsuch holders, aspring-controlled drum for each holder, a flexible connection between each holder and itsdrum, a brake, electromagnets controlling the brake, an operative connection between the springcontrolled drum, the brake and the electromagnets so disposed that each drum can turn in one direction under the action of its spring independently of the other drum and of the brake While the movement of the brake causes or allows-the simultaneous movement of both the drums for striking or feeding the are, means for limiting the amount of rotation of the drums and an electromagnet for directing the are substantially as set forth.

3. In an arc-lamp the combination of carbon-holders, converging guides for the carbon-holders, a shaft free to turn in supports, a brake-wheel on said shaft, a brake controlling the wheel, electromagnets, operative connections between the electromagnets and the brake, spring controlled drums, ratchetwheels rigidly mounted upon the shaft and each connected through a pawl to the corresponding spring-controlled drum, a flexible connection between each carbon-holder and its drum and an electromagnet for directing the are substantially as set forth.

4. In an arc-lamp the combination of carbon-holders, the converging tubes forming guides within which the carbon-holders are free to slide, plates attached to the top and bottom of said tubes and forming with them a rigid frame, supports mounted upon the bottom plate, a shaft free to turn between centers in said supports, a brake-wheel on said shaft, a'brake controlling the wheel, electromagnets mounted upon the top plate, operative connections between the electromagnets and the brake, drums rotatably mounted about fixed sleeves secured to the supports, a spring between each sleeve and its drum, ratchet-wheels rigidly mounted upon the shaft and each connected through a pawl to the corresponding spring-controlled drum,a flexible connection between each carbon-holder audits spring-controlled drum, iron rods projecting downward from the bottom plate such rods being part of an electromagnet for directing the arc and also forming a support for a globe-carrier, substantially as set forth.

5. In an arc-lamp the combination of carbon-holders,converging tubes forming guides within which the carbon-holders are free to slide, plates attached to the top and bottom of said tubes and forming with them a rigid frame, supports mounted upon the bottom plate, a shaft free to turn between centers in said supports, a brake-wheel on said shaft, a weighted arm rotatably mounted upon the shaft, a pivoted lever on said arm, a brakechain passing around the wheel and having one end attached to the pivoted lever and the other fastened to the weighted arm, electromagnets mounted upon the top plate, an operative connection between the other end of the pivoted lever and the electromagnets, drums rotatably mounted upon fixed sleeves secured to the supports, a spring between each sleeve and its drum, ratchet-wheels rigidly mounted upon the shaft and each connected through a pawl tothe corresponding spring-controlled drum, a flexible connection between each carbon-holder and its springcontrolled drum, iron rods projecting downward from the bottom plate, such rods being part of an electromagnet for directing the arc and also forming a support for a globe-carrier substantially as set forth.

6. In an arc-lamp, the combination of a frame consisting of top and bottom plates, converging tubes connected to said plates, carbon-holders within said tubes, an electromagnet for directing the arc comprising two rods extending through the bottom plate and pole-pieces connectedto said rods,and a globe carrier secured to the ends of the rods, substantially as set forth.

7. A frame for an arc-lamp, consisting of top and bottom plates, two converging tubes extending from one of said plates to the other and each having its ends connected to both said plates,carbon-holders sliding within said tubes, and controlling mechanism for the carhon-holders attached to the top and bottom plates and contained in the space between them, substantially as set forth.

In testimony whereof we have signed our names to this specification in the presence of two subscribing witnesses.

JOHN OWEN GIRDLES'IONE. CARL FREDERIK v GRIlllUlt THORKELIN.

Witnesses:

HARRY B. BRIDGES, ARCHD. J. FRENCH. 

